Damper construction



Dec. 4, 1945. w s sMlTl-l l 2,390,227.

DAMPER CONSTRUCTION De@ 4, 1945^ 2 w. s. SMITH I DAMPER CONSTRUCTION Filed July 3l, 1944 2 Sheets-Sheet 2 Patented Dec. 4, 1945 UNITED STATES :PATENT OFFICE DAMPER YWil-li'amfS. Smith, Hinsdale, Ill., assignor to Henry Pratt Company, a corporation of Illinois Application July v431, 1944, Serial No. 547,496

9 Claims.

This invention relates to damper construction and more particularly 'to a construction in which a series of parallel louver blades are turned vsimultaneousl'y, in the same direction, -from open to closed position.

The primary object of the present invention is to provide an improved damper construction which will be easy to operate, offer little resistance to the iiow of air in the open position, and be substantially air-tight when in closed position.

The construction is particularly adapted to large installations, such as wind tunnels, aircraft testing structures and the like, where the opening is sometimes about eight feet long and the louver blade six feet in length. With such large installations, the edges of the blade usually make a friction contact with a stationary part of the structure when in closed position, and considerable force is required to overcome this friction when it is necessary to open the damper. An important feature of the present invention is the use of rollers between pairs of adjacent blades which facilitate making a tight closed connection with the fiexible edges of the blades.

Another object of the invention is to provide an improved yielding contact between the ends of the bladesand the frame when in closed psition.

The invention is illustrated in a preferred embodiment in the accompanying drawings in which- Figure l is a fragmentary elevational View of a damper construction, embodying the invention, in open position; Fig. 2, an end elevational view of the actuating mechanism for the blades; Fig. 3, a fragmentary sectional view taken at line 3 3 of Fig. l; Fig. 4 a fragmentary sectional view taken as indicated at line 4 4 of Fig. 3; Fig. 5, a fragmentary sectional view taken as indicated at line 5-5 of Fig. 3; Fig. 6 an enlarged fragmentary sectional view of a portion of one of the blades; and Fig. '7, a fragmentary sectional view taken as indicated atline 'l-'l of Fig. 5.

In the embodiment illustrated, a frame Il may be formed of Vertical channel members 9 reinforced by an I-beam I0, and joined by channel members II in which louver blades I2 and rollers I3 are journalled.

Each of the louver blades has a square shaft I4, which extends through a bearing I5 and is provided with a crank I6, connected to an adjustable actuating bar Il, which is driven by crank arm I8 from a source of power not shown. The actuating bar Il serves to rotate each of the louver blades simultaneously in the same l`direction. As shown "in Fig. 6, the louver 'blades are provided at their edge portions with a strip of yielding material such as rubber or fabric I9, which is clamped in place by means of a plate .2'D`a`nd bolts 2l n y The 'channel members II at the top 'and bottom of the structure also are provided with a strip of rubber or canvas 22, whose edge portions are clamped by strips 23 held by screws 24. The ends of the louver blades are closed by triangular pieces of metal 25, which are welded to the blades and support a strip of half-round metal 25, which turns against the strip 22 when in closed position, and makes a substantially airtight connection.

As shown in Figs. 3 and 4, the rollers I3 are provided at each end with bearings 2l, so as to turn easily when brushed on opposite sides by the louver blades I2. The rollers are provided on opposite sides with deectors 28, which are reinforced by crossbars 29, and are closed at their ends by triangular strips 30, which are bolted to the channel II as indicated at 3l.

It will be understood that at each end of the frame a mutilated louver blade must be provided. As shown in Fig. 3, this blade is the same as the blades I2, except that one leg of the blade is cut away and a rubber sealing strip 32 is secured near the center of the blade to engage the channel 9 when the blade is in closed position, as indicated by the dotted line in Fig. 3.

As will be clear from Fig. 3, when the louver blades are turned from the open position illustrated to the closed position, indicated by dotted lines, the yielding edge of one blade brushes one side of the roller while the yielding edge of the adjacent blade brushes the roller at a diametrically opposed line, and both blades tend to rotate the roller counter-clockwise, as viewed in Fig. 3. In opening the louvers the roller again facilitates movement. It will be understood that the blades may be turned readily from closed position to full open position, or any desired intermediate position.

The foregoing detailed description is given for clearness of understanding only, and no unnecessary limitations should be understood therefrom, for some modifications will be obvious to those skilled in the art.

I claim:

1. In a damper construction: a frame, a pair of parallel louver blades spaced apart at least the width 0f a blade and journalled in said frame and provided at their edge portions with flexible contact material, and a roller journalled in said frame between said blades to rotate slightly when the blades are turned to closed position, at which time the flexible edges of the blades contact the roller.

2. A structure as specified in claim 1, in which means is provided for oscillating the blades in the same direction simultaneously, and a stationary wind deector is provided for the roller.

3. In a damper construction: a frame, a plurality of oscillatable parallel louver blades spaced apart between their centers of rotation a distance somewhat greater than the width 0f a blade and journalled in said frame, means for oscillating said blades simultaneously in the same direction, and rollers journalled in said frame between adjacent pairs of blades to be engaged at diametrically opposed lines by the edges of adjacent blades and turn therewith when the blades are turned to closed position.

4. Apparatus as specified in claim 3, in which the lateral edge portions of the blades are faced with iiexible material, and the end portions of said blades make a yielding contact with the frame.

5. Apparatus as speciiied in claim 3, in which the rollers are provided with stationary Wind deflectors, and the blades are tapered towards a. widened axis portion to reduce wind resistance when in open position.

6. In a damper construction: a frame; a plurality of oscillatable louver blades journalled in the frame for selectively swinging to closed and open position, each adjacent pair of said blades being spaced apart a distance such that when their adjacent edges are nearest together they will have a space therebetween; and a roller in each of said spaces, said adjacent edges of the blades when in their nearest together position contacting the roller therebetween.

7. Damper construction as claimed in claim 6, in which each of said rollers is provided with a stationary wind deector,

8. Damper construction as claimed in claim 6, in which each of the blade edges that contacts a roller has secured thereto flexible material to make a tight closed connection with the roller when in contact therewith.

9. Damper construction as claimed in claim 6, in which each of said rollers rotates slightly as the adjacent blade edges approach and recede from their nearest together position..

WILLIAM s. SMITH. 

